My colleague and mentor Brenda Moon, who has died aged 79, was the former librarian of Edinburgh University and the first woman to head a Scottish university library. Brenda was a slightly built and softly spoken woman who cared about others and was always gentle and supportive. However, beneath this deceptive exterior there was a clarity of thought and purpose, and a persistence which moved mountains.

One of her paradoxical strengths was that everyone underestimated her, although the intelligent only ever did that once. For Brenda, everything was prepared; no counter-argument was unanticipated; no set of facts unreadied; no odds too great. And no argument was lost, other than temporarily. Her staff revelled in the unlikely victories that she won.

She was born in Newcastle-under-Lyme, Staffordshire, educated in Birmingham and went to St Hilda's College, Oxford, to read classics. She worked in the university libraries of Sheffield (1955-62), Hull (1962-79) and Edinburgh (1980-96).

At Hull, at the Brynmor Jones Library, she served as deputy librarian under Philip Larkin, who wrote a poem, The Daily Things We Do, which he laid on her desk in February 1979 on the occasion of the 50th anniversary of the library's opening. It was Larkin who supposedly gave her the monicker "the steel snowdrop".

Brenda's early interest in library automation at Hull was developed at Edinburgh, which, under her guidance, became the first major university library in the UK to tackle the huge issues of scale in delivering a computer-based service.

She was a strong proponent of collaboration and a co-founder of the Consortium of University Research Libraries. She clearly foresaw the importance of international collaboration a decade before the internet made all libraries global. She encouraged her staff to be active and engaged professionally, to have lively minds and new ideas. At the same time she was also a powerful advocate of the importance of building special collections and archives and bringing the papers of poets and commercial companies to the university.

Brenda gained her MPhil in 1987 from Leeds University with a thesis on the naturalist Marianne North, and later her PhD, on the novelist Amelia Edwards, from Hull. She was also one of the few librarians honoured as a fellow of the Royal Society of Edinburgh. After retirement, she travelled widely with her sister, Mary, and took up photography, as well as continuing with academic research.

It was characteristic of Brenda that when she was diagnosed with an inoperable tumour, she felt first regret that she would not be able to finish her research, and secondly sorrow for the doctor who had had to break the news.